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Function only decoders in Bachmann 158

I am looking to install a TCS Fleetlighter in the unpowered end of a Bachmann 158 in order to control the lights. I have used a Lenz decoder in the powered end connected as per Steve Jones' advice at:

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This works well without any change to the resistors on the lighting circuit board. The TCS page at:

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however, suggests that the 470 ohm resistors on the lighting board be replaced with 1000 ohm versions. Is this strictly necessary? The output of the functions is rated at 250mA so if the DC voltage was 16V, minus 1.4V for the LED, this would give a current of 31mA which is well within the scope of the max output current.

Or am I missing something obvious?

ROB

Reply to
Robert Flint
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the resistor is to protect the LED which will have a max current of around

20 mA for standard LED's (less for smaller ones)

the increase in resistance is to cover you from the change from 12v to

16-18v on ddc.

on the other hand an output of 250 mA is capable of running 12 of so LED's (thoughts of a loco with lights to shame a mods scooter)

Andrew Carr

Reply to
Andrew Carr

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